A mandoline helps pair potatoes with baked haddock

This past summer I fell in love with a kitchen gadget that has been relatively slow to catch on in the U.S. – the mandoline.

I’ve had several of these kicking around my kitchen for a while now, but I never quite saw the need for them. For those not in the know, a mandoline is shaped like a plank with a very thin, very sharp blade at the far end. To use it, you slide a firm vegetable back and forth along the plank. Each time you slide over the blade, it shaves a slice off the vegetable.

Many models are adjustable, allowing you to quickly and easily create slices ranging from 1/4 inch to paper thin. Which is nice, but so what? I have good knives and a good food processor, both of which slice nicely.

Except the mandoline isn’t simply a manual food processor, and it is so much more precise than a knife. Food processors usually are too robust to produce ultrathin slices. And knives – at least in most home cooks’ hands (including my own) – simply can’t produce consistent results.

I discovered the difference this summer when on a whim I decided I wanted thinly shaved garlic in a salad. I used a knife on the first clove and didn’t get even close to what I wanted. A processor was out of the question for something so small. So I grabbed the mandoline and carefully rubbed the clove back and forth over the blade. In seconds I’d reduced it to thin shavings that perfectly flavored my salad.

Suffice to say, I am hooked. So as I contemplated a fresh approach to “breaded” and baked haddock, I turned again to the mandoline to render a potato fit for pairing with the fish. In any other form, potatoes would be too robust for a delecate baked fish.

Just one caution – there is a reason mandolines come with a hand guard for holding the vegetables while slicing. They are extremely sharp, and it’s easy to cut yourself.

Roasted Potato-Wrapped Haddock

Start to finish: 25 minutes

Servings: 4

1 tablespoon canola or vegetable oil

2 medium Yukon gold potatoes

1 tablespoon Dijon mustard

1 tablespoon mayonnaise

Salt and ground black pepper

Dried thyme

1 1/4 pounds haddock fillets (about 2 large fillets)

Heat the oven to 400 degrees F. Add the oil to a large cast-iron skillet (large enough to accommodate both haddock fillets in a single layer), then place the skillet in the oven to heat.

Meanwhile, use a mandoline or food processor fitted with the thinnest slicing blade to slice the potatoes into thin rounds. The potato rounds should be as close to paper thin as possible. Set aside.

In a small bowl, mix together the mustard and mayonnaise. Set aside.

Remove the skillet from the oven and carefully cover the bottom of it with a single layer of potato slices, overlapping the edges slightly. Season the potatoes with a bit of salt, pepper and thyme.

Use paper towels to pat dry the haddock fillets, then brush the mustard-mayonnaise mixture over both sides of the fish. Place the haddock over the potatoes in the skillet, then arrange a second layer of potato slices over the fish, covering it entirely. Season the potatoes with salt, pepper and thyme, then mist them with cooking spray.

Return the skillet to the oven and bake for 14 minutes. Increase the oven to broil and cook for another 2 to 3 minutes, or until the potatoes are nicely browned. Divide the haddock into 4 pieces, being careful to leave the potatoes in place as you serve the fish.